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Week 8: Stay hydrated when exercising by keeping a water bottle close by


Dr Ui May Tan opf the Vhi advises against over-hydration

Dr Ui May Tan opf the Vhi advises against over-hydration

Dr Ui May Tan opf the Vhi advises against over-hydration

Welcome back - I hope your training is going well and that you are feeling the physical and mental benefits that come with regular exercise.

Today I want to address the issue of making sure you strike the right balance when it comes to hydration. Correct hydration when conducting any form of exercise is really important.

When you run, or exert yourself, you sweat.

The more you sweat, your blood volume decreases making your heart work harder to deliver oxygen to the working muscles.

The best way to keep yourself well hydrated is to drink little and often throughout the day rather than downing a one litre bottle of water just before you go out for a run or walk.


When you are not engaged in exercise, a general rule of thumb is to keep a bottle of water close by - on your desk, in your handbag, wherever works for you - and to drink from it continuously throughout the day.

But what about over-hydration? Research has shown that runners are more likely to be over-hydrated than dehydrated.

This condition is called 'hyponatraemia', and is a result of having low blood sodium levels and is actually one of the most common medical complications in long distance training and racing.

Signs and symptoms of over-hydration are similar of those of dehydration, and can include confusion or disorientation, headache, muscle weakness, nausea and vomiting.

Over-hydration can be caused by someone drinking too much water during exercise or can be caused by medication being taken or an underlying medical condition which can increase thirst.


As per my first article, if you've got an under-lying condition or are taking medication, you should consult your medical practitioner for any advice on your particular condition.

To get the balance right regarding hydration when you're exercising, the latest advice is to drink according to your thirst - take a few small sips of a drink when you feel thirst and again follow the mantra of drink little and often.

So what are good options for drinking on the go?

Obviously water is a good option and is accessible.

Sports drinks can also offer a few advantages, in that they replace some of the sodium and other minerals such as chloride, magnesium, potassium and calcium that your body loses via sweat and can also provide an extra energy source for working muscles.

This doesn't mean you have to spend lots of money on pre-made sports drinks - there are lots of recipes online that you can mix up at home and bring with you on some of your longer training sessions.

Fingers crossed, the weather will get better in the weeks ahead so don't forget to keep hydration on your training check-list and you'll pass the water test with flying colours on June 1.